Operation Merchant of Venice

This was the Allied capture of Myitkyina in the north of Japanese-occupied Burma (17 May/3 August 1944).

The success was achieved by the forces of Lieutenant General Joseph W. Stilwell’s Chinese Army in India (‘X’ Force, otherwise Lieutenant General Sun Li-jen’s New 1st Army, centred on the New 22nd Division, New 30th Division and New 38th Division) supported by the 14th Division, 50th Division and 1st Tank Battalion, Colonel Charles N. Hunter’s US 5307th Composite Unit (Provisional) of the Northern Combat Area Command, and Brigadier J. M. Calvert’s Indian 77th Brigade in the aftermath of its involvement in the ‘Thursday’ 2nd Chindit Expedition.

Myitkyina was held by elements of Lieutenant General Masaki Honda’s 33rd Army, and was of strategic importance not only because of its rail and water links to the rest of Burma, but also because it was on the planned route of the Ledo Road.

When the South-East Asia Command was established in August 1943, Stilwell was appointed deputy to Admiral the Lord Louis Mountbatten, commander of the SEAC. Taking command of various Chinese and Allied forces, including a new US Army special operations formation, Brigadier General Frank D. Merrill’s 5307th CU(P) which arrived in October with the codename 'Galahad' Force, Stilwell built up his Chinese forces for an eventual offensive into northern Burma. On 21 December 1943 Stilwell assumed direct control of planning for the invasion of northern Burma, which was to culminate in the capture of Myitkyina. In the meantime, Stilwell ordered the 5307th CU(P) to embark on long-range jungle penetration missions behind Japanese lines after the pattern of the ‘Chindits’.

In February 1944 three battalions of the 5307th CU(P), totalling 2,503 men and 250 mules, started on their 1,000-mile (1610-km) overland advance from north-eastern India into northern Burma across the eastern Himalaya mountains and the Burmese jungle. Stilwell’s thinking was proved essentially correct by a significant victory over Lieutenant General Shinichi Tanaka’s 18th Division at Maingkwan and Walabum during the first week of March 1944: while the Chinese attacked the Japanese defensive positions from the front, the 5307th CU(P) carried out a wide flanking movement, partially severing the Japanese lines of communication at Walabum, and inflicting heavy losses on the Japanese. Only by a rapid withdrawal and skilful delaying actions was Tanaka able to save his division from destruction.

Stilwell repeated this tactic in a larger sweeping envelopment to get behind the Japanese at Shaduzup in the hills of the Jambu Bum, separating the Hukawng and Mogaung valleys. This time a Chinese regiment accompanied one battalion of the 5307th CU(P) while the remainder of the Chinese pinned the strong Japanese defensive positions along the Jambu Bum. Again the Japanese were decisively defeated, and two regiments were trapped. But in a desperate battle between 28 March and 1 April Tanaka and his men fought their way out of the encirclement. Tanaka moved quickly to establish a new line across the upper part of the Mogaung valley.

A counterattack on an exposed battalion of the 5307th CU(P) was repulsed only with some difficulty, and the Americans were besieged for several days in the mountain village of Nhpum Ga before they were relieved by a combined ground and air attack. During these operations the Chinese and US troops were maintained entirely by air supply furnished by Major General Howard C. Davidson’s US 10th Air Force from the ‘Hump’ bases in upper Assam, most of the supplies being delivered directly by air drops into jungle clearings immediately behind front line units.

As the front moved farther to the south, an advance air base was built at Shingbwiyang, where additional supplies were stored for later delivery by aircraft and trucks. Then, totally unexpectedly, Stilwell discovered that the sources of his forces’ air supply, and thus the continued existence of these forces, gravely threatened. The Japanese had begun their long-planned ‘U’ invasion of Manipur, achieved considerable initial success to take Kohima and Imphal under siege, and were approaching the vital Bengal-Assam railway, which was the lifeline of the North Combat Area Command and the ‘Hump’ airlift. Stilwell ordered a temporary delay in the north Burma offensive, and sent an extemporised task force to help the British secure the vital railroad artery in Assam.

While most of his troops paused in the Mogaung valley awaiting the outcome of ‘U’, on 3 April Stilwell met Lieutenant General W. J. Slim, commander of the British 14th Army, in an emergency conference at Jorhat in Assam. Stilwell offered to send the Chinese New 38th Division back to help, but Slim declined the offer, assured Stilwell that the situation around Kohima and Imphal would soon be under control, and urged Stilwell to resume his Chinese-American offensive in northern Burma.

Confident of Slim’s abilities, Stilwell immediately followed his advice. It was about this time that Stilwell was able to persuade Generalissimo Chiang Kai-shek, the Chinese nationalist supremo, to send two more divisions to join his army in Burma. Of these the 50th Division was one of the best in the Chinese army, and soon justified its reputation in combat in Burma. The other formation was the 14th Division, which was not of the same calibre. While these two new divisions were being re-equipped in Assam and north Burma, the New 38th Division and New 22nd Division resumed their advance in the Mogaung valley, but their progress was very slow.

Stilwell suspected that the divisional commanders were under secretly orders from Chiang to delay their advance as the generalissimo was less confident than Stilwell in Slim’s reassurances. Stilwell therefore decided to carry out a plan he had long been contemplating, namely a blow directly at Myitkyina, the northern terminus of the railway from Rangoon to northern Burma via Mandalay, before the start of the spring monsoon. Near Myitkyina was the only hard-surfaced airfield in northern Burma, and the seizure of this airfield would prevent the Japanese from continuing their sporadic harassment of the ‘Hump’ airlift, and would also permit the ‘Hump’ route to be moved to the south and thereby operated over a more direct route which also offered the advantage of transit over less formidable mountains. Furthermore, capture of the strategically located town would be a major step toward breaking the blockade of China by pushing forward the Ledo Road and its oil pipeline.

On 28 April the 5307th CU(P) and elements of the New 30th Division, a force of about 7,000 men, started on a bold advance to the east from the Mogaung valley over the high Kumon mountains. Using trails known only by their Kachin guides, the Allied task force secretly made its way slowly but steadily through country normally considered impassable by organised fighting units. Arriving in the Irrawaddy valley, the advance continued to Myitkyina, where the US and Chinese force seized the main airfield on 17 May in a surprise attack. Chinese reinforcements were promptly flown in, even though the field was still under small arms fire.

On 18 May the Allied troops attacked Myitkyina itself, which was currently held by no more than 700 Japanese. But Allied errors, resulting largely from disease, exhaustion and an over-eagerness which had already reduced the Allied strength to fewer than 3,000 men, allowed this weak garrison to throw back the assault. For a few days the reinforcements were barely able to keep pace with losses from combat, illness and exhaustion. Had the Japanese realised this, they might have been able to inflict a disaster on the floundering Allies, since the prompt assembling of outlying Japanese detachments had given them almost equal effective strength. Yet the US and Chinese troops managed to maintain pressure on the Japanese defences, now led by Major General Genzu Mizukami, and threw back numerous counterattacks.

News of the initial success at Myitkyina spurred the lethargic 22nd and 38th Divisions to increased activity in the area to the north of Kamaing. Another spur was the aggressive example of the 149th Regiment, of the freshly arrived 50th Division, which had been attached to the 22nd Division. On May 25, a regiment of the 38th Division carried out a bold envelopment to establish a roadblock behind the Japanese lines at Seton, on the road between Kamaing and Mogaung.

Tanaka responded with his usual coolness and vigour. Gathering his reserves and all the 18th Division’s ‘tail’ personnel, he surrounded the Chinese at Seton and launched a series of counterattacks. But the Chinese were well versed in the checking of such counterattacks and, maintained by air supply, drove back the Japanese attacks. At the same time Tanaka’s front-line units were being slashed by a series of envelopments and frontal attacks by the revitalised 22nd and 38th Divisions.

Meanwhile, on 17 May, just before they withdrew from their last railway block at ‘Blackpool’, the ‘Chindits’ had come under the operational control of the Northern Combat Area Command. After the ordeal of their ‘Thursday’ second expedition, the Chindits had pulled back into the mountains to the west of Kamaing, around Lake Indawgyi, where they were regrouping and recuperating as they waited for an opportunity to return to rest areas in India. Stilwell now called upon them to join in a concentric movement against the area of Kamaing and Mogaung. Major General W. D. A. Lentaigne, who had taken command after the death of Major General O. C. Wingate in an air crash on 24 March, protested that his men were too exhausted to take effective action. But Stilwell insisted and Lentaigne reluctantly complied, moving part of his command against the left flank of the 18th Division.

Early in June the 22nd Division, spearheaded by the attached 149th Regiment, closed on the 18th Division’s positions at Kamaing. Harassed by the ‘Chindits’ to his west, and the Seton roadblock to his south, Tanaka was unable to stem the determined Chinese advance across the monsoon-flooded Indaw river. During a driving storm on 16 June the 149th Regiment led the 22nd Division into Kamaing in a bayonet charge which drove the defenders out of the city in confusion. On the following day units of the 38th Division crossed the Mogaung river to the south of Kamaing to relieve the defenders of the Seton roadblock, who had been isolated for more than three weeks.

The hard-hit 18th Division had lost most of its artillery and been reduced to less than half strength by casualties and sickness, and now withdrew around the Seton block toward Mogaung. But even in this disastrous situation, Tanaka remained at the top of his tactical game. A Chinese battalion pursued too closely, and lost contact with neighbouring units in the jungle, and spotting an opportunity, Tanaka turned his units and struck the battalion from two directions and practically destroying it, before continuing the withdrawal.

Meanwhile, in compliance with Stilwell’s orders, Calvert’s Indian 77th Brigade of the ‘Chindits’ had cut across the rear of the 18th Division and on 22 June attacked the defences of Mogaung from the south-east. In a pitched battle totally alien to Wingate’s concept of ‘Chindit’ combat, the dogged British and Gurkhas of the Indian 77th Brigade slowly fought their way into the town, which fell on 26 June when the 38th Division arrived from the north. The Chinese quickly moved to the east along the road linking Mogaung and Myitkyina and established a land link with the Chinese and US forces laying siege to Myitkyina. A few weeks later than he had planned, Stilwell had secured the vital heart of northern Burma.

To the great anger of Stilwell, who had been promoted to full general on 1 August 1944, Myitkyina itself was still holding out and now became the focus of Allied and Japanese attention in northern Burma. By the beginning of June sufficient reinforcements and supplies had been flown into the Myitkyina airfield to make it possible for the Allies to blockade the western approaches to the town, and thus the so-called siege was not a complete investment. The Japanese lines of communications across the Irrawaddy river to the east remained open despite some harassment by a Chindit detachment and by British- and US-led Kachin guerrillas. Using this line of communications, the Japanese received a constant trickle of supplies and reinforcements from Bhamo.

The strength of the garrison had grown to nearly 3,500 by a time early in June, and at much the same time the Allied force had grown to about 35,000 men. The principal components of the Allied investment force were the Chinese 14th, 30th and 50th Divisions, and a mixed group of US units. This force was commanded by Brigadier-General Haydon L. Boatner, who apparently both underestimated Japanese strength and overestimated the capability of his own force. To Boatner’s annoyance, therefore, the repeated Allied attacks were thrown back by the well-entrenched garrison. The results were no different even after several pieces of artillery had been delivered by air to bolster the attacks that fighter-bombers were making on the defence.

Part of Boatner’s problem had been a sudden collapse of the 5307th CU(P), whose men had entered combat early in March believing that their tour of duty was to last only three months. This period had now elapsed, and the 5307th CU(P) had been on the march or engaged in desperate battles, usually against superior numbers and usually behind the Japanese lines, for almost this whole time. The US soldiers expected fulfilment of the ‘promise’ they believed had been made to them. Stilwell and Boatner had made no such promise, and knew that no one else had done so, at least at the official level. The US commanders also knew that there was a critical battle to be fought, and the outcome of the entire campaign depended on success at Myitkyina. The generals expected the 5307th CU(P) to remain their spearhead and set an example for the Chinese divisions. Furthermore, it was politically impossible for Stilwell to pull Americans out of the fight when he was demanding renewed efforts from the British near Mogaung.

The result was the morale of the 5307th CU(P) plummeted: the sick rate soared, men fell asleep firing their weapons, and aggression disappeared from patrolling and battle. Stilwell had no option but to pull the 5307th CU(P) out of the front line and, in order to maintain a US component in the siege, withdrew two US engineer battalions from their work on roads and airfields and rushed them to Myitkyina. Unprepared both psychologically and militarily for such a sudden introduction to battle, the engineer battalions suffered heavy casualties and their performance was adequate rather than good. Stilwell also was able to find a few men of the 5307th CU(P) to strengthen and indoctrinate of a new US infantry regiment created as ‘New Galahad’ using replacements arriving in the theatre. The regiment was soon received its final lesson in waging war on the Japanese in the trenches in front of Myitkyina.

The Japanese skilfully checked the ineffectual Allied thrusts, exacting severe casualties for each yard of soil they yielded. Thus the siege dragged on for week after week, and Boatner, whose ill-advised goading had managed to antagonise Chinese as well as US officers, fell ill and was succeeded by the softer-spoken but nonetheless tough Brigadier General Theodore F. Wessels. There followed a period of reorganisation as Wessels reinvigorated the besieging force, and then the attack was resumed.

Now much degraded by disease, losses and an increasing shortage of supplies, the Japanese had to fall back from the outskirts of Myitkyina. General Masamitsu Kawabe, the commander of the Burma Area Army, who was to be succeeded on 30 August by General Heitaro Kimura, was more than satisfied with the delay which had been imposed on the Allies by the protracted siege of Myitkyina and, as part of a general reorganisation of the Japanese forces in Burma at this time, finally ordered the defenders to withdraw. This the Japanese accomplished with great skill on 3 August, although they suffered some losses as a result of a simultaneous Allied attack. Mizukami, who had been promoted to full general two days earlier, committed suicide.

After a blockade and a battle of more than 11 weeks, Myitkyina was finally in Allied hands. Some 600 Japanese escaped, and about 3,000 had been killed in the siege. The Allied casualties were 972 Chinese and 272 US troops killed, 3,184 Chinese and 955 US troops wounded, and 188 Chinese and 980 US troops, of whom 570 were men of the 5307th CU(P), evacuated sick.

Only a week after the fall of Myitkyina, the 5307th CU(P), down to only 130 combat-effective men from the original strength of 2,997 men, was disbanded. Only a week after the fall of Myitkyina, the 5307th CU(P), down to only 130 combat-effective men from the original strength of 2,997 men, was disbanded.

Despite delays and tactical setbacks, however, Stilwell’s strategy had been vindicated. US engineers were rushing the road and pipeline across the Hukawng valley, and Stilwell was therefore close to breaking the land blockade of China. The elimination of Japanese air opposition from north Burma was already being reflected in a sharp rise in tonnage delivered over the ‘Hump’: despite the monsoon, this tonnage increased from 13,686 tons in May to 25,454 tons in July.